Need more info, was it a 305 TBI? or a 305 TPI? TBI was rated @ 170HP the TPI was rated @ 220HP and the 5.7 @ 240HP. my 90' 5.7 ran 14.27 @ 96+ stock, and with bolt ons it went 13.4 @ 102MPH on drag radials, it had stock 327 gears, and a stock 1800 converter, no motor work at all, but had headers, cats removed, Flowmaster, cold air induction, pullys,Welds up front 205-65-15's,ETC, the basic stuff!! my buddys 5.0 TPI, auto ran 13.9's with bolt ons and 373's. TBI's more like high 15's or low 16's, I had one it ran high 15's and it was an automatic, the only mods were: ADS superchip, cat removed and a Flowmaster 2 chamber muffler, hope this helps.
JAY
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98'Trans Am LS1 273 gears Whisper lid,K&N,Whisper MAF ends,Flowmaster,Best ET on street tires 13.17 @ 106.49mph